Effect of γ-irradiation on optical properties of Eu2 O3 -doped polystyrene polymer films

Luminescence. 2018 Nov;33(7):1243-1248. doi: 10.1002/bio.3541. Epub 2018 Aug 24.

Abstract

In the present study, europium (III) oxide (Eu2 O3 )-doped polystyrene (PS) polymer films were synthesized using a solution-casting technique for different filler levels. These films were irradiated with 5, 25 and 50 kGy γ doses and characterized using various techniques, viz. X-ray diffraction (XRD), and UV-visible and photoluminescence (PL) spectroscopies as a function of composition level and radiation dose. The UV-visible spectra indicated a decrease in the optical direct band gap of composite films with increasing concentrations of dopant and radiation dose. The band gaps of composites obtained using Tauc's equation were found to be 4.38, 4.37, 4.36 and 4.34 eV for 0, 1, 3 and 5% Eu2 O3 -doped PS respectively, while the band gaps of 5% Eu2 O3 -doped PS polymer films irradiated with 5, 25 and 50 kGy were found to be 4.30, 4.26 and 4.21 eV, respectively. Photoluminescence (PL) emission spectra showed the characteristic peaks of Eu3+ at 595 nm, 612 nm and 617 nm with an excitation wavelength of 247 nm. The intensity of characteristic peaks of Eu3+ was observed to increase with increasing filler concentration, while it was found to decrease with increasing radiation dose. The polymer under study may be useful in accidental dosimetry. As photoluminescence studies are carried out after a gap of 200 h from irradiation and PL emission of γ-irradiated polymer yielded 10 times emission when compared with non-irradiated polymer.

Keywords: Europium (III) oxide; Photoluminescence (PL); Polystyrene (PS); UV-visible; γ-Irradiation.

MeSH terms

  • Europium / chemistry*
  • Gamma Rays
  • Luminescent Agents / chemistry*
  • Polystyrenes / chemistry*
  • X-Ray Diffraction

Substances

  • Luminescent Agents
  • Polystyrenes
  • Europium

Grants and funding